Actor Jake Gyllenhaal surprised patients at a Boston hospital on St Patrick's Day while he was in the city researching film locations.
The 35-year-old actor visited Spaulding Rehabilitation Hospital in Charlestown on in preparation for his upcoming movie "Stronger", in which he stars as Boston Marathon bombing survivor Jeff Bauman, reported People magazine.
Jeff lost both of his legs in the April, 2013 bombings, and was the subject of a graphic viral photo, showing his badly injured limbs as he was being wheeled to an ambulance after the explosion, which killed three and left hundreds injured.
The Boston native, who had been waiting at the finish line for his girlfriend, Erin Hurley, as she competed in the annual race, later helped investigators identify the suspects, brothers Dzhokhar and Tamerlan Tsarnaev, from his hospital bed.
Gyllenhaal has been extensively researching his role as the bombing survivor, making visits to various Boston hospitals and rehabilitation facilities, as well as spending time with Jeff himself.
"He was touring the hospital, just checking things out. They're just checking out locations and people from the book, and Jeff had been cared for here," a representative for the hospital said.
During his tour of the facility, Gyllenhaal met 24-year-old patient Jenna Laing, 24, who was recovering after suffering a serious spinal injury.
"Stronger" will be based on Jeff's memoir of the same name and co-star Tatiana Maslany as his now-wife.
Production is due to begin in April, with David Gordon Green as director.
"Stronger" is one of three films about the Boston Marathon bombings currently in development. Mark Wahlberg is also working on one of the movies, titled "Patriots' Day".
