When the Cowboys took a 20-3 lead into the half, they had held Calvin Johnson in check. Tony Romo had played an excellent first half, completing 19-of-24 passes for 195 yards and two touchdowns -- both to Dez Bryant.
The second half even started out well for Dallas, as Romo threw his third touchdown pass of the game, this time to Jason Witten from one yard out, giving Dallas a commanding 27-3 lead.
That's as good as it would get for the Cowboys on Sunday, as the wheels came flying off the wagon.
Romo would throw his first interception of the day to former Cowboy Bobby Carpenter, which Carpenter returned 34 yards for Detroit's first touchdown of the game, cutting Dallas' lead down to 27-10.
Detroit's defense wasn't done, though. With the score still at 27-10, Romo was intercepted again, this time by Chris Houston, which he returned 56 yards for a touchdown.
Romo would lead Dallas' offense on a drive inside Detroit's five yard line, but, the Cowboys were unable to convert on third down and were forced to settle for a 23 yard field goal from Dan Bailey. Jason Garrett had opted to go for it on 4th-and-goal from Detroit's one earlier in the first quarter, and Felix Jones was stopped short.
Trailing 30-17, Calvin Johnson finally showed up in the end zone. Matthew Stafford connected with Megatron on a 23 yard touchdown pass, cutting Dallas' lead down to 30-24 with over 13 minutes left to play.
Once again, though, Dallas' offense stalled out, and the Lions capitalized again. Jason Hanson booted a 51 yard field goal, making the score 30-27 with just over four minutes to play.
Immediately, Romo was intercepted by Stephen Tulloch on a pass intended for Witten. The Lions capitalized on Romo's third interception, as Stafford found Johnson again -- this time from two yards out, capping off Detroit's comeback.
Dallas will head into their bye week with a 2-2 record -- with both losses representing fourth quarter meltdowns as the Cowboys had the Jets on the ropes in Week 1, before fourth quarter mistakes facilitated New York's comeback.
The loss overshadows the fine play of Laurent Robinson, who was targeted 10 times by Romo. Robinson finished the day with seven receptions for 116 yards.
Dallas' defense played well, holding Stafford in check. Stafford completed 21-of-43 for 240 yards, two touchdowns and an interception.
Jason Garrett's team will now take the week off before preparing to take on Tom Brady and the New England Patriots in Week 6.