As she enters St Patrick's church for Midnight Mass on Christmas Eve, her mind remembers a similar church in war-torn London, in March 1944. Colleen and three other nurses are sight seeing while on a three-day pass and when they enter the Savoy, she runs into an attractive Army Air Force Captain. Time is suspended as the intensity of emotions swirls around them. But then he leaves as she enters, and the moment is lost.

While enjoying the sounds and companionship at the "Muscle Palace", a dance hall for the troops, Daniel berates himself for not asking the name of the young woman he collided with at the Savoy. He frantically searches the dancers, hoping against hope that she will be there.

Colleen also scans the patrons of the dance hall, wishing the man at the Savoy had at least asked for a name. Amid ribbing from her friends, she accepts a bet whether or not she will see the mystery pilot again while in London. As one of the other nurses tells her she must sing in the talent show for the patients if she loses, Daniel catches a glimpse of Colleen and makes his way across the room.

In the middle of their first dance, the bandleader breaks in with news that the air raid sirens are sounding, and they must exit to the bomb shelter. While waiting out the raid, Colleen and Daniel get to know the basics of each other, and Daniel witnesses first hand the competency and compassion of these nurses as an injured woman stumbles into the shelter. He falls for her when she sings "Someone To Watch Over Me" to the children.

After Daniel walks Colleen back to her hotel, she realizes she has fallen for this flyboy, but doesn't know if she can take the pain of losing another love to this war. When her roommate returns, they talk about the pros and cons of loving someone while serving their country and the dangers they all face. Colleen decides not to worry about what may or may not happen, and instead, should enjoy spending whatever time she can with Daniel.

Daniel takes Colleen to Greenwich Park and gives her a tiny, silver angel with the inscription "Someone to Watch Over You" on the back of the brooch. She then gives him the gift of a pilot's wings bracelet with "A Pair of Wings to Safely Guide You Home" engraved on the name tag. The gifts touch them both, heart and soul, and Daniel proclaims his love for Colleen.

At the talent show, Daniel and his pilot buddies offer their rendition of the Andrews Sisters, while Colleen walks away with a thunderous roar of applause and the winner's trophy. They receive the news that one of nurses is going to marry Daniel's friend. With this information, Daniel hints at Colleen that getting married sounds like a good idea.

Several weeks later, Daniel takes Colleen to Glastonbury and proposes. She refuses and explains that she loves him, but the war prevents her from becoming his wife; she can't lose someone else to the violence of war. Daniel pleads with her to see that if they don't take the chance of happiness today, it may be gone tomorrow, and they'll be left with nothing but regrets and empty memories. Colleen accepts his proposal when she realizes that it would hurt more to be without him forever, than to love him and lose him.

Just a week before they're to be married, Daniel visits Colleen with news for her newlywed friend--her husband, and Daniel's flying buddy, was killed in action. After seeing the devastation his death has on the nurse, Colleen tells Daniel she cannot marry him.

It is now several days before Christmas 1944, and the Battle of the Bulge is in full force. Colleen is stationed in a field hospital somewhere near the French-Belgian border, and Daniel is flying Mustangs near the French coast. Over the past several months, they have kept in contact and have managed to see one another while on pass in Paris. But Colleen hasn't changed her mind about marrying Daniel.

He haunts her dreams, and her worry for his safety increases as the push to the German border intensifies. Every wounded soldier she sees bears his face. Whenever she hears a new patient is a pilot, her heart freezes with the fear it may be Daniel. Colleen is expecting him for a brief visit the next day, and suddenly she realizes that her love for him is greater than the fear of what may happen. She's looking forward to spending Christmas with him and telling him just how much she loves him and what a fool she's been these past few months.

The day Daniel came to tell Colleen's friend of her husband's death relives itself as a pilot that flies with Daniel comes to see Colleen. He tells her that Daniel's plane was shot down over Bastogne and he was reported as missing in action. She refuses to believe the worst and holds out hope that he is alive. Several days pass, and it's now Christmas Eve, with still no word about Daniel. Colleen attends the service at a local church and prays for Daniel's safe return. She vows to never let a day go by without Daniel knowing she loves him and swears never to let him out of her life.

On her way back to the hospital, someone calls her name, and out of the blinding snow walks a figure. It's Daniel. They vow never to be separated again and plan to marry the next day. After the ceremony, Daniel explains what happened after he was shot down, and tells Colleen that he traded the pilot's wings bracelet for her Christmas gift--a glass angel. He promises Colleen he will always be with her.

Saddened by the memories, Colleen leaves St Patrick's Church and returns home. Since Daniel's death six months ago, she has lost hope and misses him deeply. Every year of their marriage, he has left the gift of a glass angel on her pillow after Midnight Mass. Only this year, there would be no angel and the loss hurts. When she returns home, lying on her pillow is a small gift-wrapped box. With shaky fingers, she opens the box and tears fall down her face.

Colleen lifts out a pilot's wing bracelet with the words "A Pair of Wings to Safely Guide You Home" engraved on one side and Daniel's name on the other. It is the same bracelet she had given Daniel in Greenwich Park fifty-seven years before. In that instant, she knows he never left her, and would always be in her heart. He was her guardian angel and with the gift of a pair of wings, he brought hope and love back into her life.